This is a program project dealing with the structure and regulation of membrane-bound enzymes. Space does not allow for adequate summary. BIBLIOGRAPHIC REFERENCES: Structure of the Adduct Derived from the Inhibition of Monoamine Oxidase by 3-Dimethylamino-1-propyne, Alan L. Maycock, Robert H. Abeles, James I. Salach, and Thomas P. Singer in Flavins and Flavoproteins (T.P. Singer, ed.), Elsevier, Amsterdam, 218-224 (1976). Cysteinyl Flavin in Monoamine Oxidase from the Central Nervous System, J.I. Salach, T.P. Singer, K.T. Yasunobu, N. Minamiura, and M.B.H. Youdim in Monoamine Oxidase and Its Inhibition (Ciba Foundation Symposium), (J. Knight, ed.), Elsevier, Amsterdam, pp. 49-56 (1976).